1. Technical Field
The present disclosure relates generally to fiber optic cables used in telecommunication systems, and in particular relates to cable assemblies for fiber optic cables, and more particularly relates to bi-directional cable assemblies arranged at mid-span access locations and that have one or more optical fiber tethers.
2. Technical Background
Optical fiber is used for a variety of broadband telecommunication applications that involve voice, video and/or data transmissions. Such fiber-based telecommunication systems utilize fiber optic cables (e.g., “distribution cables”) that include a number of mid-span access locations at which one or more optical fibers are terminated and interconnected with a branch cable or a drop cable. The mid-span access locations provide an interconnection point, also referred to as “access point” or “tap point” (or just “tap” for short) from the distribution cable. The interconnection point can include a cable assembly that connects optical fibers in the distribution cable to another location, such as another network distribution cable or termination point, or directly to an end user, commonly referred to as a “subscriber,” thereby extending an “all optical” communications network closer to the subscriber. In this regard, fiber optic networks are being developed that deliver “fiber-to-the-curb” (FTTC), “fiber-to-the-business” (FTTB), “fiber-to-the-home” (FTTH), or “fiber-to-the-premises” (FTTP), referred to generically as “FTTx.”
An example application of a fiber-based telecommunication system is an intelligent transportation system (ITS) that utilizes sensors and video cameras to monitor traffic conditions. The data from such monitoring are transmitted to a centralized data gathering facility via a fiber optic cable. The typical data gathering network architecture for the ITS is a ring or loop topology that provides bi-directional connectivity to the monitoring equipment. The present approach to connecting the monitoring equipment to the fiber optic cable is to use two taps, each tap having its own separate tether and connector. This arrangement has the disadvantage of requiring that a tether be on both the upstream and downstream directions of the fiber optic cable. The tether facing the direction in which the fiber optic cable is pulled while being installed requires special protection to prevent it from being torn from the fiber optic cable during installation. To date, using a single connector has not been a practical alternative to the two-connector approach because it would require the fiber in the downstream side of the cable access point to be bent back 180 degrees to allow it to fit into the tether of the cable assembly. Conventional optical fiber technology restricts the bending diameter of the fibers in the fiber optic cable to no less than 30 mm to 40 mm to prevent bend-induced attenuation loss in the fiber. Unfortunately, having to preserve large bend radii at the tap point renders the tap point too large to deploy without damaging the tether.